Digital Trends – The national wireless carrier space will grow smaller by one when AT&Tâs acquisition of T-Mobile moves forward, and regional carriers have been stepping up their own games. MetroPCS, the number five wireless provider in the United States, actually beat Verizon to the punch in rolling out the first domestic 4G LTE network. Now, number six contender U.S. Cellular is following suit, with plans to launch its own 4G LTE service by the end of this year.